Scriba brings structured logging to Guile Scheme

Scriba is a Guile Scheme library that provides structured logging with four built-in backends: plain console, color console, syslog, and JSON for Loki or Datadog [Lobsters]. The library implements a macro-based logger that expands at compile time, moving most of the formatting work out of the hot path [Codeberg]. Logger instances are cached, and creating a logger with the same configuration anywhere in the code returns a pre-initialized object instantly. Dynamic log context is attached via a parameterize form, allowing nested metadata without runtime allocation overhead. The auto-configured logger picks the appropriate backend based on environment variables, so developers can run with a colored console logger locally and switch to JSON-structured output in production without code changes. Benchmarks show a 12% reduction in CPU usage compared to a naïve format-based logger in a micro-benchmark that emits 10k logs per second [Lobsters]. Scriba's JSON backend lets operators ship Guile processes directly into Loki or Datadog pipelines, closing a gap that previously forced teams to write custom adapters [Codeberg].